The present invention relates to an analogue alarm electronic timepiece which is simple in arrangement.
In this specification, although a quartz oscillator type of analogue alarm electronic timepiece will be described as a specific example, the present invention is applicable to a timpiece having another type of time standard system or a table clock.
FIG. 1 illustrates one example of a block diagram of the conventional analogue alarm electronic timepiece. An oscillating circuit 1 produces a high frequency signal as a time standard signal. A frequency dividing circuit 2 divides down the high frequency signal and produces a signal which is necessary for operating the following circuits. A driving circuit 3 synthesizes an output signal from the frequency dividing circuit 2 and periodically generates driving pluses with proper pulse width. A motor 4 converts the driving pulses into a mechanical motion. A gear train 5 and a hand (display mechanism 6) are used for transmitting the mechanical output from the motor 4 and displaying the time, respectively. An alarm time setting mechanism 8 is a provided for setting and displaying an alarm time, and the setting and displaying operation is carried out by moving an alarm setting wheel or a sub-hand which is operated by operator. A coincidence detecting mechanism 7 is a switch mechanism operated in relation to the gear train 5 and the alarm time setting mechanism 8. The fact that the present time is coincident with an alarm time, is detected in accordance with the ON-OFF condition of the switch mechanism, and an electric signal is produced. An alarm circuit 9 synthesizes an alarm driving signal on the basis of the output signal from the frequency dividing circuit 2, and the circuit 9 outputs the alarm driving signal when the coincidence detecting mechanism 7 detects the fact that the present time is coincident with the alarm time. An alarm device 10 is a piezoelectric element or an electromagnetic type of electricacoustic transducer which converts the alarm driving signal into a sound and the sound is made.
The above mentioned analogue alarm electronic timepiece is disadvantageous in that since the mechanical construction of the alarm time setting mechanism 8 and the coincidence detecting mechanism 7 are complex, it is difficult to obtain a small size timepiece or a thin-type timepiece, and the cost of manufacture is high. Moreover, since a special display device is required for setting and indicating the alarm time, it is not possible to freely decide the outer-look design for a timepiece. Furthermore, in such an analogue alarm electronic timepiece, since the coincidence detecting mechanism 7 is a mechanical switch, it is difficult to exactly set an alarm time in the unit of minute or second.